“In the United States the number of deaths that occur each year because of the disparity, not because of [just] breast cancer, is 1,700,” said Steven Whitman, director of the Institute. “That's about five a day.”

Chicago was among the worst cities, with black women in the city 61 percent more likely to die than white women. Memphis had the largest disparity, and three other cities fared worse than Chicago: Denver, Houston and Los Angeles. All of the data are based on the years 2005-2007.

The study authors have connections with the Metropolitan Breast Cancer Task Force, whose research indicates that societal factors – “racism,” as Whitman bluntly put it – are mainly responsible for the disparity. Task force members say unequal access to screening mammograms is largely to blame, and point out that Illinois' program providing screening to low-income women is nearly broke. Other public health researchers note that genetics likely plays a significant role in the race gap as well.